1. Field of the Invention
The present invention relates to a new and improved method and apparatus for packing an inflatable air cushion in a housing of an air bag module assembly of a motor vehicle restraint system. More particularly, the present invention relates to a new and improved method and apparatus for folding an inflatable air bag cushion and inserting the folded cushion into a housing in a quick and efficient manner so that a rapid inflation of the air bag cushion can be assured when the system is activated in the event of an emergency. The method and apparatus of the present invention is especially designed and adapted for use with "Pillow" type air bag cushions which generally resemble a pillow in construction and appearance when inflated and which are suitable for use in a passenger side air bag module assembly.
2. Background of the Prior Art
Kitagawa et al U.S. Pat. No. 5,324,070 discloses an air bag device for a knee of an occupant in a vehicle adapted to extend transversely of the vehicle when inflated in front of the occupants' legs from a location offset from the center of the occupant. Opposite longitudinal ends of the air bag cushion are first folded over onto a bag surface opposite a bag filling inlet which is located off center with respect to the ends. Longitudinally extending side portions of the air bag cushion are next folded over onto the same bag surface followed by successive folding over of both of the opposite end portions of the bag toward the filling inlet bag.
Kuretake et al U.S. Pat. No. 5,364,126 discloses a specially folded air bag cushion and inflator of circular outline having a central filling opening and a pair of eccentric vent openings on a side opposite an occupant cushioning surface. From a flat position with the cushioning surface on top, an edge portion of the bag is folded over along a line in one direction so that the vent openings face upwardly and a portion of the edge portion away from the vent openings is folded over to cover the same. Thereafter an opposite edge portion of the bag is folded over in similar fashion followed by folding over opposite portions of the bag from opposite ends along lines generally normal to the first direction so that the air bag will initially fill along the first direction and thereafter along the second direction. The air bag is finally put into a pleated condition in the housing.
Fischer U.S. Pat. No. 5,275,435 discloses an air bag cushion which is folded into a pleated condition from both top and bottom portions and has a first folded portion which pivots and moves sideways as the air bag cushion inflates to direct the vehicle occupant to one side. The air bag cushion is folded to create side pleats which are tucked to the inside of the air bag cushion which is rolled up from both ends.
Webber U.S. Pat. No. 5,348,341 discloses a method of folding an air bag cushion wherein each side is folded twice with all four folds overlapping and then is rolled for insertion into the module housing with a flap positioned over the roll.
Bollaert U.S. Pat. No. 5,290,061 discloses a folded air bag cushion that is tucked up from the bottom inside the air bag cushion and then pleated, rolled, or a combination of pleating and rolling action is used to bring in the sides.
Wehner et al U.S. Pat. No. 5,240,282 discloses an air bag folding technique wherein an air bag cushion is pleated from the bottom, then folded and pleated horizontally and inserted into the housing. The pleats along vertical lines do not overlap from opposite sides but meet adjacent the center.
Zelanak, Jr. et al U.S. Pat. No. 5,022,675 discloses an air bag folding technique wherein the sides are pleated inwardly and the side pleated bag is then rolled up for insertion in the module housing.
McArthur U.S. Pat. No. 4,286,954 discloses a method of folding an inflatable restraint cushion for storage in a support housing wherein an overlying top sheet and an underlying bottom sheet of the cushion are placed in a taut condition between the housing and an imaginary line parallel thereto. A portion of the top sheet is successively moved toward the housing so as to form a series of overlying pleated sections which are progressively shorter in length and eventually rotating the pleated cushion as a unit into a cavity of the housing.
Wullbrecht U.S. Pat. No. 3,738,477 discloses an air bag cushion which is rolled up to create a bubble which acts as a restraint to prevent sudden upward movement during inflation as successive rolled up layers are inflated resulting in a smaller frontal mass first moving into contact with the occupant.
Kornas et al U.S. Pat. No. 3,839,947 discloses apparatus for tucking and rolling a vehicle occupant air bag cushion which is clamped under tension while tucked from the ends and then is rolled up.
Bell U.S. Pat. No. 4,529,396 discloses apparatus for forming a rolled tubular fabric article.
Putti et al U.S. Pat. No. 3,839,948 discloses apparatus for rolling a vehicle occupant air bag into a stored condition including a pair of carriers for clamping an air bag on opposite sides of a diffuser and movable toward the diffuser to roll up opposite portions of the bag.
Kelley U.S. Pat. No. 5,178,407 discloses a folded air bag having a first portion with a plurality of folds in stacked relation providing a surface area for engaging a vehicle occupant upon air bag inflation and a second portion with a plurality of folds in stacked relation providing a surface for engaging the vehicle windshield.
Baker U.S. Pat. No. 5,162,035 discloses a bag folding system in which pleats are created on the sides of an airbag, these pleats are then tucked inside the air bag cushion, and the cushion is rolled up to create a final bag pack.